The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 03, 2015
Filed:
Jan. 10, 2012
Takahiro Mitsumori, Tokyo, JP;
Takeru Kinoshita, Tokyo, JP;
Hirotoshi Ise, Tokyo, JP;
Asahi Glass Company, Limited, Tokyo, JP;
Abstract
A glass substrate-holding tool employed during the production of a reflective mask blank for EUV lithography includes an electrostatic chuck and a mechanical chuck. A caught and held portion of a glass substrate caught and held by the electrostatic chuck, and pressed portions of the glass substrate pressed by the mechanical chuck are located outside a quality-guaranteed region on each of a film deposition surface and a rear surface of the glass substrate. The sum of a catching and holding force applied to the glass substrate by the electrostatic chuck and a holding force applied to the glass substrate by the mechanical chuck is at least 200 kgf. A pressing force per unit area applied to the glass substrate by the mechanical chuck is at most 25 kgf/mm.